COATS 7xxx Series Tire Changer - Manual (Page 20)

16 • Important: Always read and follow operating instructions.
Performance, Custom and
Aluminum Wheels
CAUTION
Only tire technicians with experience and
training on custom wheels should attempt
to service expensive custom alloy or alu-
minum wheels and high-performance low-
profile tires.
Pre-Operation Notes:
• Ensure all weights have been removed.
• Clamp wheel from the outside.
• Use ample lubricant for mount and demounting.
• Always review wheel nicks and/or scratches with
the owner before servicing.
Performance Tires and Wheels • Demounting
Follow these instructions for performance type tires
and wheels, including run-flat tires and their associated
wheels, and asymmetrical hump wheels.
1. Remove valve core and completely deflate tire.
2. Pull the bead loosener shoe away from the machine
and roll the tire into position against the bumper pads.
Position the tire with the valve stem in the 2 o’clock
position (in direct line with the bead loosener shoe).
Always loosen the bead on the narrow/mounting side
of the wheel first (figures 2 and 28).
Figure 28 - Position Tire for Bead Loosening
AA. Wheels with an asymmetrical hump have a
larger “ledge” type hump around the wheel except
at the valve hole making them more difficult to
mount and demount (figure 29). Always loosen the
beads near the valve stem on both sides of rim.
Figure 29 - Asymmetrical Hump Wheel
AB. Some wheels/tires have a low pressure sensor/
transmitter strapped to the wheel (figure 30). This
is especially true on run-flat tire/wheel systems.
The sensor is positioned directly opposite from the
valve stem. Other low pressure warning systems
have the sensor as part of the valve. To avoid dam-
aging the sensor, always loosen the top bead with
the valve stem at the 2 o’clock position first, then
loosen the bottom bead with the valve stem at the
2 o’clock position, and then continue to loosen the
remaining circumference of the beads as neces-
sary. Avoid loosening at 180 deg. (opposite) the
valve.
Figure 30 - Wheel with Low Pressure Sensor/Transmitter
3. Loosen bottom bead, starting with valve stem at
2 o‘clock position next to the loosener shoe (figure 31).
Figure 31 - Loosen Bottom Bead
Valve Stem
Smooth
Hump
At Valve
Hole
Ledge
Hump -
Rest of
Wheel
Valve Stem
Sensor